Problem: A 39-year-old married ex-nurse was referred by her general practice doctor to psychiatric outpatient clinic with a 6-month history of depressed mood. She was a slim woman of medium height who had been suffering from tearfulness, lack of energy, anhedonia, reduced appetite and weight loss. She was suffering from initial insomnia of 1-2 hours but there was no early morning wakening. She had also noticed that her menstrual cycle, which was normally regular, had stopped 3 month ago. Prior to referral her physical condition had been extensively investigated by an endocrinologist and all test had proved negative. Although the patient was suffering from depressed mood, she denied having suicidal thoughts. Her husband confirmed that she had never seriously considered suicide. What is the most likely diagnosis? A. Mild depressive episode. B. Moderate depressive episode. C. Severe depressive episode without psychotic symptoms. D. Severe depressive episode with psychotic symptoms. E. Recurrent depressive disorder.